doTestNodeTypeConstraintViolation(boolean useWorkspace,
boolean useHandler)
Create a node named ntBase with node type nt:base
and creates a tree in the repository which will be exported
and reimported below the node ntBase.

doImport

Helper method which imports the given FileInputStream using Workspace or Session
and via the methods importXML respective getImportContentHandler. Teh target node of the
import is specified with its absolut path.